NO START TIMING?

1999 Toyota Corolla

I have a 1999 corolla 1.8 with 80,000 miles. The problem is it won't start. It has spark, Gas, the compression is 170 except for #4 it is 140. It backfires like it is out of time. I cheaked the chain and it it lines up according to the manual.I know the 1998 and 1999 are alone the one thing I noticed is it has the vvt timing senser but it has no plug in. Any ideas would be helpful.'Thank You

Dear Marr,
Sounds like you have a problem with number 4 intake or exhaust value. The fact that the compression for #4 cylinder is lower than the rest of the readings is leading me to believe this. Also the backfiring suggest that the intake (back firing through the throttle body) or exhaust value(through the exhaust) is leaking. I think you should do the compression test again on the #4 cylinder, except this time do a wet test. Add 2 to 3 tablespoons of motor oil through the spark plug hole before doing the compression test. If the rings are bad the compression will go up considerable. If not (this is what I think will happened) the value or values for that cylinder is bad. FYI a 4 cylinder engine may not start with one cylinder not working properly. Hope this helps Backyardmechanic : )